120 lines
3.6 KiB
JavaScript
120 lines
3.6 KiB
JavaScript
|
import { VantComponent } from '../common/component';
|
||
|
|
import { isObj, range } from '../common/utils';
|
||
|
|
const DEFAULT_DURATION = 200;
|
||
|
|
VantComponent({
|
||
|
|
classes: ['active-class'],
|
||
|
|
props: {
|
||
|
|
valueKey: String,
|
||
|
|
className: String,
|
||
|
|
itemHeight: Number,
|
||
|
|
visibleItemCount: Number,
|
||
|
|
initialOptions: {
|
||
|
|
type: Array,
|
||
|
|
value: []
|
||
|
|
},
|
||
|
|
defaultIndex: {
|
||
|
|
type: Number,
|
||
|
|
value: 0
|
||
|
|
}
|
||
|
|
},
|
||
|
|
data: {
|
||
|
|
startY: 0,
|
||
|
|
offset: 0,
|
||
|
|
duration: 0,
|
||
|
|
startOffset: 0,
|
||
|
|
options: [],
|
||
|
|
currentIndex: 0
|
||
|
|
},
|
||
|
|
created() {
|
||
|
|
const { defaultIndex, initialOptions } = this.data;
|
||
|
|
this.set({
|
||
|
|
currentIndex: defaultIndex,
|
||
|
|
options: initialOptions
|
||
|
|
}).then(() => {
|
||
|
|
this.setIndex(defaultIndex);
|
||
|
|
});
|
||
|
|
},
|
||
|
|
watch: {
|
||
|
|
defaultIndex(value) {
|
||
|
|
this.setIndex(value);
|
||
|
|
}
|
||
|
|
},
|
||
|
|
methods: {
|
||
|
|
getCount() {
|
||
|
|
return this.data.options.length;
|
||
|
|
},
|
||
|
|
onTouchStart(event) {
|
||
|
|
this.setData({
|
||
|
|
startY: event.touches[0].clientY,
|
||
|
|
startOffset: this.data.offset,
|
||
|
|
duration: 0
|
||
|
|
});
|
||
|
|
},
|
||
|
|
onTouchMove(event) {
|
||
|
|
const { data } = this;
|
||
|
|
const deltaY = event.touches[0].clientY - data.startY;
|
||
|
|
this.setData({
|
||
|
|
offset: range(data.startOffset + deltaY, -(this.getCount() * data.itemHeight), data.itemHeight)
|
||
|
|
});
|
||
|
|
},
|
||
|
|
onTouchEnd() {
|
||
|
|
const { data } = this;
|
||
|
|
if (data.offset !== data.startOffset) {
|
||
|
|
this.setData({ duration: DEFAULT_DURATION });
|
||
|
|
const index = range(Math.round(-data.offset / data.itemHeight), 0, this.getCount() - 1);
|
||
|
|
this.setIndex(index, true);
|
||
|
|
}
|
||
|
|
},
|
||
|
|
onClickItem(event) {
|
||
|
|
const { index } = event.currentTarget.dataset;
|
||
|
|
this.setIndex(index, true);
|
||
|
|
},
|
||
|
|
adjustIndex(index) {
|
||
|
|
const { data } = this;
|
||
|
|
const count = this.getCount();
|
||
|
|
index = range(index, 0, count);
|
||
|
|
for (let i = index; i < count; i++) {
|
||
|
|
if (!this.isDisabled(data.options[i]))
|
||
|
|
return i;
|
||
|
|
}
|
||
|
|
for (let i = index - 1; i >= 0; i--) {
|
||
|
|
if (!this.isDisabled(data.options[i]))
|
||
|
|
return i;
|
||
|
|
}
|
||
|
|
},
|
||
|
|
isDisabled(option) {
|
||
|
|
return isObj(option) && option.disabled;
|
||
|
|
},
|
||
|
|
getOptionText(option) {
|
||
|
|
const { data } = this;
|
||
|
|
return isObj(option) && data.valueKey in option
|
||
|
|
? option[data.valueKey]
|
||
|
|
: option;
|
||
|
|
},
|
||
|
|
setIndex(index, userAction) {
|
||
|
|
const { data } = this;
|
||
|
|
index = this.adjustIndex(index) || 0;
|
||
|
|
const offset = -index * data.itemHeight;
|
||
|
|
if (index !== data.currentIndex) {
|
||
|
|
return this.set({ offset, currentIndex: index }).then(() => {
|
||
|
|
userAction && this.$emit('change', index);
|
||
|
|
});
|
||
|
|
}
|
||
|
|
return this.set({ offset });
|
||
|
|
},
|
||
|
|
setValue(value) {
|
||
|
|
const { options } = this.data;
|
||
|
|
for (let i = 0; i < options.length; i++) {
|
||
|
|
if (this.getOptionText(options[i]) === value) {
|
||
|
|
return this.setIndex(i);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return Promise.resolve();
|
||
|
|
},
|
||
|
|
getValue() {
|
||
|
|
const { data } = this;
|
||
|
|
return data.options[data.currentIndex];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|